High-efficiency lead-free CH3NH3SnI3 perovskite solar cell with inorganic transport layers: SCAPS-1D and PVSyst-Based numerical study

Perovskite solar cells (PSCs) have emerged as a promising photovoltaic technology due to their high efficiency, tunable bandgap, and low-cost fabrication. However, challenges such as lead toxicity, suboptimal architecture, and defect-induced recombination continue to hinder the large-scale commercialization of PSCs. In this study, a comprehensive numerical analysis of an FTO/STO/CH₃NH₃SnI₃/NiO/Au device was performed using SCAPS-1D, complemented by PVSyst modeling to assess module-scale performance. Critical parameters—including absorber and ETL thickness, absorber doping density, intrinsic recombination coefficients, defect densities, and resistive losses—are systematically investigated. The device architecture achieves a simulated power conversion efficiency of 30.72 % (V_oc = 1.2159 V, J_sc = 28.39 mA/cm², FF = 89.00 %) under AM 1.5G illumination, approaching the Shockley–Queisser limit for its 1.3 eV bandgap. Sensitivity analysis reveals that the CH₃NH₃SnI₃ absorber and its interface with STO are the most defect-sensitive regions, where excessive defect densities drastically reduce efficiency, while NiO and other interfaces remain defect-tolerant. Optimal performance is further linked to low radiative (≤10⁻¹³ cm³/s) and Auger (≤10⁻³³ cm⁶/s) recombination, as well as minimal series resistance (≤1 Ω cm²) and high shunt resistance (≥10⁵ Ω cm²). PVSyst simulations confirmed the scalability of the device architecture to a 72-cell module, while underscoring the need for thermal management to mitigate V_oc and PCE losses at elevated temperatures. These results highlight that precise control of structural parameters, defect passivation—especially at the absorber/ETL interface—and resistive loss minimization can enable high-efficiency, environmentally benign PSCs with performance nearing the theoretical efficiency limit.